1. Field of the Invention
The present invention relates to a controller and method for controlling interfacing to a data link.
2. Description of the Prior Art
To facilitate communication between products, it is known to develop standardised interfaces specifying the format of communications over a data link between those products. The standardised interface may be designed to facilitate the handling of multiple data streams over the data link, with each data stream relating to a particular data element. Often, the data link is partitioned, for example in time or frequency, to define a number of data slots, with particular data elements being assigned to particular data slots. By this approach, data relating to a plurality of different data elements can be transmitted over the data link at the same time.
For example, in the area of codecs (coder-decoders), Intel have developed an interface protocol for interfacing to codec chips. This interface protocol defines the format for a communications data link between a codec chip and any product, which is to communicate with that chip. More particularly, this interface protocol defines a digital data link employing a serial TDM (time division multiplexing) format for handling multiple input and output data streams. According to this protocol, the link architecture divides each audio frame into a number of data slots, with particular data elements (for example left channel audio, right channel audio, headset, modem, etc) being assigned to particular data slots.
Generally, for any particular application, a controller will be developed, which interfaces to the codec via the above described data link. Since, in any particular application, it is usual for only a subset of the data slots to be used, the controller will generally be developed having regard to the particular application. Whilst this helps to reduce the complexity of the controller, it often means that a different controller needs to be developed for each application.
However, this has generally been considered a more preferable approach than attempting to produce a generic controller, since such a generic controller would appear to require separate data buffering circuitry for each data slot supported by the data link specification, thereby increasing the size and cost of such a generic controller.
It is the aim of the present invention to provide a generic controller in which such size and cost problems are alleviated.